Again he said, “To what shall I compare the kingdom of God? It is like yeast that a woman took and mixed in with three measures of wheat flour until the whole batch of dough was leavened.”Luke 13:20-21
As in the parable of the mustard seed which precedes the parable of the yeast, the kingdom of God expands slowly and gradually from something minuscule.
Yeast is a single-celled microorganism in the kingdom of fungi. It takes 20,000,000,000 (twenty billion) yeast cells to weigh one gram.
Three measures of wheat flour, on the other hand, is a huge quantity equivalent to about nine gallons or thirty-six quarts, enough to feed up to three hundred people. Jesus’ reference to three measures of wheat flour immediately rang a bell in Hebrew minds. Abraham asked his wife Sarah to prepare a meal for three visitors from three measures of flour. The word for measure in Jesus’ parable (Greek saton) is a direct translation of the Hebrew seah in the story of the first patriarch.
Abraham hurried into the tent to Sarah and said, “Quick, three measures of fine flour! Knead it and make bread.”Genesis 18:6
Such an extravagant amount of bread expressed the magnanimous hospitality of Abraham and Sarah toward God himself.
The Lord appeared to Abraham by the oak of Mamre, as he sat in the entrance of his tent, while the day was growing hot. Looking up, he saw three men standing near him.Genesis 18:1-2a
In Eastern Christian icons of the hospitality of Abraham, the three guests are depicted as three angelic beings—a theophany of the Most Holy Trinity.
When Hannah brought her son Samuel to Eli the priest, she offered an ephah of flour in the house of the Lord (1 Samuel 1:24).
The Passover grain offering is specified as one ephah (Ezekiel 45:24).
The offering of a prince on Sabbaths, feasts, and festivals includes a grain offering of one ephah (Ezekiel 45:24; 46:5, 7, 11). “Prince” (nasiy’) is used in Scripture of Abraham, Solomon, rulers, chiefs, and most significantly, the future Davidic king.
Christ, the anointed priest-king and Son of David, offers himself and all of humanity to God the Father. The rising dough of three measures of flour suggests the communion of saints in the triune God permeated with the leaven of Christ and the Holy Spirit. The woman, a type of Sarah, brings to mind Mary, the humble handmaid of the Lord. The Son of God entered our humanity as a microscopic cell and is transforming it silently and unobtrusively like yeast.
The Church places herself in the loving hands of Mother Mary to knead Christ into hearts.